Introduction to Laser Physics

What is a laser?

Laser is an acronym for Light Amplification by Stimulated Emission of Radiation. Since American engineer and physicist T.H Maiman invented the first working laser in 1960, the development of other lasers followed quickly. However, within the last 2 decades, the technological advances and the use of lasers in the field of dermatology have virtually exploded. Many treatments have only become possible with the use of lasers, especially in aesthetic medicine. Due to better research and understanding of the physics of light and skin, there is now an increasing and wide array of lasers and devises to choose from such as Nd:YAG, Erbium:YAG, Carbon Dioxide (CO2), Alexandrite, Yellow, Diode, Pico etc. In 1983, a fundamental breakthrough in the understanding of laser and light interactions with the skin was published as the “Theory of Selective Photothermolysis”. Based on this theory, pulsed lasers were able to specifically and selectively target and destroy structures within the skin, without damage to surrounding tissue.

When light is absorbed, it gives up its photon to a target molecule termed a chromophore. In the skin, the three main primary chromophores are melanin, water and hemoglobin. Each of these exhibits its particular band of absorption at certain wavelength. Melanin’s absorption spectrum include mainly ultraviolet and visible light. Water, the main component of collagen, absorbs best beyond the near infrared spectra. Hemoglobin exhibits peak absorption in the UVA, blue (400nm), green (541nm) and yellow (577nm) wavelengths. Without light absorption, there can be no effect on the tissue.

Here are some common lasers and their wavelengths:

Carbon dioxide (CO2) – 10,600nm
Erbium:YAG (Er:YAG) – 2940nm
Erbium doped fibre – 1550nm
Erbium Glass – 1540nm
Q-switched Nd:YAG – 1064nm
Long pulsed Nd:YAG – 1064nm
Diode – 800, 900, 1450nm
Pulsed dye – 585, 595nm
Dual Yellow – 578, 611nm
Alexandrite – 755nm
Thulium – 2097nm
Intensed Pulsed Light (IPL) – 550-1400nm

Alexandrite laser – is a solid state laser tunable in a wavelength range 700-830 nm, normally being operated at 750nm. Alexandrite laser medium is a chromium-dope chrysoberyl and can operate in cw (up to 100W) or pulsed mode. Because light of this wavelength region is absorbed by melanin and dyes, but not significantly by blood, it can be used for the destruction of melanin-containing structures such as hair roots and pigmented lesion.

Pico laser – is a laser technology that uses short burst of energy between 1 picosend and some of tens of picoseconds for the removal of tattoos, moles, acne scars and age spots as well as the reduction of wrinkles. The most common source of picosecond laser are actively or passively mode-locked solid state bulk lasers that can provide clean ultrashort pulses with pulse repetition rates varying from a few megahertz to more than 100 Ghz.

Yellow laser – is a dermatological laser that emits both yellow light and green light simultaneously for a wide range of treatments. It is indicated for skin rejuvenation, dark eye circle, acne & acne scars, pigmentation such as solar lentigines, freckles and melasma. Yellow laser is a copper bromide thereby eradicating active acne at the same time promoting collagen growth, reducing redness & improving sensitive skin.

Indications and type of lasers which can be used for treatment:-

• Epidermal lesions (Epidermal nevus, Seborrheic keratosis, Viral warts- verruca vulgaris, plane warts)
— Carbon dioxide (CO2) laser, Erbium:YAG (Er:YAG) laser

• Dermal lesions (Angiofibroma, Keloids, Rhinophyma, Sebaceous hyperplasia, Syringoma, Xanthelesma, Melanocytic nevus- junctional, compound)
— Carbon Dioxide (CO2) laser, Erbium:YAG (Er:YAG) laser

• Vascular lesions
— Alexandrite laser, Long-pulsed Nd:YAG laser, Diode laser, Pulsed dye laser, Pulsed potassium-titanyl-phosphate (KTP) laser, Intense Pulsed Light (IPL)

• Epidermal pigmented lesions (Ephelides, Lentigines, café-au-lait macules, nevus spilus)
— Q-switched Frequency doubled Nd:YAG laser, Intense Pulsed Light (IPL)

• Epidermal and dermal (mixed) pigmented lesions (Becker’s nevus, melasma)
— Q-switched Ruby laser, Q-switched Alexandrite laser, Picosecond Alexandrite laser, Intense Pulsed Light (IPL)

• Dermal pigmented lesions (Nevus of Ota, Nevus of Ito, Hori’s nevus, Congenital nevus)
— Q-switched Nd:YAG laser

• Tattoos
— Q-switched Ruby laser, Q-switched Alexandrite laser, Picosecond Alexandrite laser, Q-switched Nd:YAG laser, Frequency doubled Nd:YAG laser

• Hair Removal
— Long-pulsed Nd:YAG laser, Diode laser, Long-pulsed Alexandrite Laser, Long-pulsed Ruby laser, Intense Pulsed Light (IPL) systems

• Ablative Laser Resurfacing
— Carbon dioxide (CO2) laser, Erbium:YAG (Er:YAG) laser

• Nonablative Photorejuvenation (Scars, Wrinkles, Photoaging, Acne vulgaris, Sebaceous hyperplasia, Skin tightening, Striae distansae, Pores)
— Q-switched Nd:YAG laser, Pulsed dye laser, Intense Pulsed Light (IPL), Erbium glass laser, Diode (1450nm) laser, Long-Pulsed Nd:YAG laser

Where to buy Medical Aesthetic Lasers in Singapore

There are a number of companies in Singapore who distribute different types of aesthetic lasers.

1. Servicom
• Cho yang: Carbon dioxide (CO2) laser
• Sciton: BBL, Long-pulsed Nd:YAG laser, Erbium:YAG (Er:YAG) laser
• Cynosure: Picosure laser

2. Venus Concept
• Asclepion: Dermablate laser, Pro Yellow laser

3. Innomed
• Syneron: Picoway laser, GentleYAG laser, GentleMax laser, GentleLASE laser
• Cynosure: Revlite laser, Medlite laser

4. Skin M.D
• Lutronic: Spectra XT laser, Clarity Alexandrite laser, Mosiac laser, eCO2 Carbon Dioxide laser
• Cutera: Enlighten laser
• Dual Yellow: Dual Yellow laser

5. Absolute M.S
• Won Tech: Lavieen Thulium laser, Cosjet ATRS Q-Switched Nd:YAG laser, Aileen Long-pulsed Nd:YAG laser

6. NeoAsia
• Alma: Soprano XL laser, Soprano ICE laser, Harmony XL laser, Harmony XL PRO laser, Legato II Microplasma laser, Accent Ultra V laser
• Dekka: SmartXide2V2LR Carbon dioxide (CO2 ) laser, SmartXide2 Dot/RF laser, Duolite Q-switched Nd:YAG laser

Aglow Aesthetics

At Aglow Aesthetics Pte Ltd, we distribute a range of medical aesthetic equipment from Jeisys and Fotona.

Jeisys (Korea)

Jeisys Medical Inc, founded in 2001, is a worldwide medical device manufacturer which produces high-end products for plastic surgeons, dermatologist, physicians, and healthcare professionals.
• Cellec IPL system
• Tri-Beam Q-switch Nd:YAG laser
• Edge Fractional Carbon dioxide (CO2) laser

Fotona (Slovenia)

Fotona’s decades-long experience in the laser industry began 50 years ago in 1964. Fotona today is a world-leading medical laser company recognized for its innovative, award-winning laser systems for applications in aesthetics & dermatology, dentistry, surgery and gynecology.
• SP Dynamis Long-pulsed Nd:YAG and Erbium:YAG (Er:YAG) laser
• SP Spectro Long-pulsed Nd:YAG and Erbium:YAG (Er:YAG) laser